A061978 - OEIS

A061978

Numbers n such that n divides the (left) concatenation of all numbers <= n written in base 25 (most significant digit on right).

143

1, 3, 9, 21, 33, 57, 96, 864, 1033, 1661, 6449, 6624, 10464, 68249, 81664, 108981, 164384, 167571, 234311, 2420409, 5490464

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OFFSET

1,2

COMMENTS

This sequence differs from A029542 in that all least significant zeros are kept during concatenation.

No more terms < 7*10^6.

LINKS

EXAMPLE

See A061955 for example.

MATHEMATICA

b = 25; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[Reverse[IntegerDigits[#, b]], c], b], #] &] (* Robert Price, Mar 09 2020 *)

CROSSREFS

KEYWORD

nonn,base,more

AUTHOR

Larry Reeves (larryr(AT)acm.org), May 24 2001

EXTENSIONS

Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002

a(20)-a(21) from Lars Blomberg, Jul 22 2011

STATUS

approved